"This guy doesn't have a clue about the middle class. Not a clue," Biden said.

"He has no clue about what makes America great — actually, he has no clue, period," Biden said.

And the crowd loved it.

But after a few jabs, Biden refocused the group for a final blow.

"Let me talk about something that I'm deadly serious about. This is a complicated and uncertain world we live in. The threats are too great, the times are too uncertain to elect Donald Trump as president of the United States," Biden said.